Method Library
The Method Library stores reusable data processing methods for DFS Pro. Use it when a fusion task or governance workflow needs repeatable logic, such as preprocessing, feature extraction, merge logic, labeling, or math operations.
Open:
Data Integration > Method Library
Method categories
| Category | Typical use |
|---|---|
| Preprocessing | Clean values, normalize units, reshape rows, prepare fields. |
| Feature Extraction | Create derived features for analytics or predictive maintenance. |
| Merge | Combine records from several datasets. |
| Label | Add labels, classes, status flags, or review tags. |
| Math | Apply calculations, thresholds, scoring, or aggregation logic. |
Built-in and custom methods
Built-in methods are provided by the platform. Custom methods are created by the tenant team for project-specific logic.
Use custom methods when:
- source data uses project-specific fields;
- an output must follow a customer naming convention;
- a fusion task needs repeatable matching behavior;
- predictive maintenance features need documented preparation logic;
- a reviewer needs to test logic before using it in a workflow.
Create a custom method
- Open Method Library.
- Select Add Method.
- Enter method name.
- Choose category.
- Add description.
- Add pseudo code that explains the logic.
- Add sample input JSON.
- Add expected output JSON when the result should be compared.
- Save the method.
Use pseudo code that a reviewer can understand. It should explain the operational logic, not only the implementation detail.
Test a method
Test a method before publishing or using it in a fusion task.
- Open the method.
- Select Test.
- Enter sample input JSON.
- Enter expected output if available.
- Run test.
- Review output, duration, rows in, rows out, and match result.
Good sample input includes:
- normal records;
- missing fields;
- boundary values;
- duplicate keys;
- values that should be rejected or flagged;
- source-specific examples from a real workflow.
Publish a method
Publish only after sample tests are acceptable.
Before publishing, confirm:
- method name is clear;
- category is correct;
- description explains when to use it;
- pseudo code is understandable;
- sample input is representative;
- expected output is correct;
- reviewer accepts the behavior.
Published methods can be used by downstream workflows such as fusion tasks.
Create a new version
Create a new version when method logic changes.
Use a new version when:
- matching keys change;
- feature calculation changes;
- source priorities change;
- tolerance or threshold changes;
- output schema changes;
- downstream workflow owners need repeatability.
Before deprecating an older version, check method usage and affected fusion tasks.
Monitor usage and performance
Method Library can show usage and performance information.
Review:
- fusion task usage count;
- harness or test runs;
- success rate;
- p50, p95, and p99 latency when available;
- recent failures.
Use this information before editing, versioning, or deprecating a method.
Example: predictive maintenance feature method
A feature extraction method might:
- read equipment ID, timestamp, vibration, temperature, and current;
- normalize units;
- calculate rolling average or rate of change;
- flag missing intervals;
- return a feature table for predictive maintenance review.
The method should be tested with sample input that includes normal data, missing intervals, and out-of-range values.
Related pages
| Page | Use |
|---|---|
| DFS Pro Datasets | Prepare input datasets for methods and fusion tasks. |
| Fusion Tasks | Use published methods in multi-source fusion. |
| Review Queue | Review uncertain outputs produced by fusion workflows. |